The purpose of the study was to investigate the bacterial viability of the initial biofilm on the surface of experimental modified dental resin composites. Twenty-five healthy individuals with good oral hygiene were included in this study. In a split-mouth design, they received acrylic splints with five experimental composite resin specimens. Four of them were modified with either a novel polymeric hollow beads delivery system or methacrylated polymerizable Irgasan (Antibacterial B), while one specimen served as unmodified control (ST). The delivery system based on Poly-Pore® was loaded with one of the active agents Tego® Protect 5000 (Antiadhesive A), Dimethicone (Antiadhesive B) or Irgasan (Antibacterial A). All study subjects refrained from toothbrushing during the study period. Specimens were detached from the splints after 8h and given a live/dead staining before fluorescence microscopy. Friedman test and post-hoc Nemenyi test were applied with significance level at p < 0.05. In summary all materials but Antibacterial B showed a significant antibacterial effect compared to ST. In conclusion dental resin composites with Poly-Pore loaded active agents show antibacterial effectiveness in situ.

Helicobacter pylori, a gram-negative bacteria usually found in stomach and first part of small intestine, is known to cause infections and ulcers and may have association with cancer. Normally, the treatment options include combinations of antibiotics with proton pump inhibitors and antiinflammatory drugs. However, all of them have high systemic exposure, and hence, unfavourable side effects, whereas their exposure in stomach mucus, the predominant location of the bacteria, is very limited. We have attempted to develop a predominantly gut-restricted formulations of antibiotic + adjuvant combinations as a basis for potentially more safe and efficacious treatment of gastrointestinal tract infections. We have considered E. coli (as a model of H. pylori) and Lactobacilli to study the antibacterial activity of nanogel with combined drugs (classical antibiotics and individual components of essential oils). It has been shown that levofloxacin (LF) in combination with zephirol demonstrates synergy effect against E. coli (cell viability has decreased by about 50%) and weakens the effect against Lactobacilli. A number of other combinations of antibiotic + adjuvant is also shown to be effective. Using FTIR and UV spectroscopy, it has been proved that chitosan nanogels with the drug are well adsorbed on the mucosal model, thereby increasing the bioavailability of drugs. Using ABTS assay, the antioxidant properties of flavonoids and other drugs are shown, which is potentially necessary to minimize the harmful effects of toxins and radicals produced by pathogens. Thus, chitosan nanogels loaded with a combination of drugs can be considered as a new strategy for the treatment of infectious diseases of the gastrointestinal tract, and applicable to difficult-to-treat bacteria.

Biosurfactants (BSs) are microbial compounds that have emerged as potential alternatives to chemical surfactants due to their multifunctional properties, sustainability, and biodegradability. Owing to their amphipathic nature and distinctive structural arrangement, biosurfactants exhibit a range of physicochemical properties, including excellent surface activity, efficient critical micelle concentration, humectant properties, foaming and cleaning abilities and the capacity to form microemulsions. Furthermore, numerous biosurfactants display additional biological characteristics, such as antibacterial, antifungal, and antiviral effects, antioxidant, anticancer, and immunomodulatory activities. Over the past two decades, numerous studies have explored their potential applications, including pharmaceuticals, cosmetics, antimicrobial and antibiofilm agents, wound healing, anticancer treatments, immune system modulators and drug/gene carriers. These applications are particularly important in addressing challenges such as antimicrobial resistance and biofilm formation in clinical, hygiene, and therapeutic settings. They can also serve as coating agents for surfaces, enabling antiadhesive, suppression, or eradication strategies. Not least importantly, biosurfactants have shown compatibility with various drug formulations, including nanoparticles, liposomes, micro and nanoemulsions, and hydrogels, improving drug solubility, stability, and bioavailability and enabling targeted and controlled drug release. These qualities make biosurfactants promising candidates for the development of next-generation antimicrobial, antibiofilm, anticancer, wound healing, immunomodulating, drug or gene delivery agents, as well as adjuvants to other antibiotics. Analyzing recent literature, this review aims to provide insights into the present understanding, highlight emerging trends, identify promising directions and advancements in the utilization of biosurfactants within the pharmaceutical and biomedical fields.